There are roughly 3,036 textual differences between Sinaiticus and Vaticanus in the Gospels:
Matthew: 656
Mark: 597
Luke: 791
John: 1022
70-80% of these differences are due to the presence or absence of the movable nu. The movable nu is a grammatical feature in Greek where the letter ν is added to the end of certain words (e.g., verbs or nouns) when the following word begins with a vowel or to avoid hiatus (a gap between vowels). This is an orthographic or stylistic difference that does not impact meaning in any way.
Here is an example:
Vaticanus: λέγειν (with movable nu)
Sinaiticus: λέγει (without movable nu)
The next largest portion of differences is spelling differences such as:
Vaticanus: Ζαρε (Zare)
Sinaiticus: Ζαρα (Zara)
Here again, there is absolutely no impact to meaning. This is also seen in English versions like the KJV where you will see Boaz and Booz.
Thirdly, we find order differences such as:
Vaticanus: Ἰησοῦς Χριστός (Jesus Christ)
Sinaiticus: Χριστός Ἰησοῦς (Christ Jesus)
Like the other examples, this type of difference has no impact on meaning or whatsoever.
The remaining differences are omissions or additions of phrases or clauses. Since Vaticanus aligns closely with the Alexandrian Family of manuscripts and Vaticanus is closely related to the Western Family of manuscripts, we should expect some variation in the same way we see differences in Byzantine manuscript families.
In summary, the vast majority of these 3,036 differences in the Gospels are non-impactful in any way to the text. The substantive differences are common between various manuscript families across both all lines (Byzantine, Alexandrian, Western, etc.).
If anyone has questions about a particular variant, I will be happy to try and address it.
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